Method of reinforcing tubular structures.



Patented Jan. 12, '1909.

nu G F L M Wmo O A n D /////////M/M/M.M

1N: Nonms PETERS ca.. wAsnmaraN, n. c,

H. H. HILBORN & C. E.. ROEHL.

APPLIUATION FILED MAY 22, 1908.

' METHOD OP REINFORGING' T-UBULAR STRUCTURES.

, down around the base of the same.

NTTED STATES lill.

HERBERT H. HlLBORN AND CHARLES E. ROEHL, OF NEW YORK, N. Y.

METHOD OF REINFGRCING- TUBULAR STRUCTURES.

Application filed May 22, 1908.

To all lwhom 'it may concern:

Be it known that we, HERBERT H. HIL- BoRN and CHARLES E. Ronin., citizens of the Dominion of Canada and the YUnited States, respectively, and residents of the borough of Brooklyn, county of Kings, city and State of New York, have invented certain new and useful lm rovements inlvlethod of Reinforcing Tubu ar Structures, of which the following is a specification, accompanied by drawings.

This invention relates to a new and imroved method of reinforcing tubular or holow structures and it also relates to the structure so reinforced.

The invention is particularly adapted for reinforcing metallic trolley poles, which are generally of tapering form, smaller at the top than at the bottom, but the invention may be used in any connection in which it is found ap licable, and it is not limited in its use to tro ley poles.

The invention also contemplates the reinforcing of structures of lighter material than would normally be required, because the reinforcement supplies the additional strength. The lighter outer covering would be sufficient to withstand the abrasion and ordinary wear and tear to which trolley poles and similar structures are subjected, while the reinforcement would add the required strength. ln this way the cost of such structureswould be reduced, because it would not be necessary to use the heavy material.

It has been found by experience that a trolley pole becomes weakened at the ground line in the course of time, because water and secretions of various kinds collect at this oint, causing the metal to rust, and because of the effect of electrolysis. ln consequence the pole may become so greatly weakened that it will break at or near the ground line, due to the weight of the trolley wire and its connections and the forces acting at the top of the pole to bend the pole.

Various means have been resorted to in order to strengthen trolley oles at the ground line, as for instance, y slipping a metallic sleeve over the top of the pole and The cost of such a sleeve is expensive and if not inserted in place when the pole is first installed, the time, labor and cost of placing these sleeves on the poles after they have been installed is prohibitive, owing partly to the fact that the trolley wire connections Specification of Letters Patent.

Patented Jan. 12, 1909.

serial No. 434,281.

must be removed at each pole before the sleeve can be slipped over the pole, and then the connections must be again attached to the pole.

p Our improved method of reinforcing trolley poles is adapted for use in connection with old poles which have been installed, and our invention obviates the necessity of removing the trolley wire connections from the poles, because we reinforce the poles from the inside instead of the outside. Our method can be used by simply removing the cap at the` top of the pole and replacing the cap after1 the reinforcement has been inserted in the p ln one embodiment of our invention we insert a flexible frame or core into a pole and expand said frame or core therein. We then embed the frame or core in concrete or other cementitious material, by filling the pole or the desired portion of the same with said material. These operations or steps are all carried out without the necessity of interfering in any way with the trolley system itself.

The objects of our invention are therefore to enable trolley poles or other similar structures to be reinforced from the inside, without interfering in any way with parts which may be attached to or supported upon the outside of the structure. pand the reinforcing frame or core within the pole, because the reinforcing frame should lie as near as possible to the walls of the pole. Then if the outer shell of the pole should break or crack at or near the ground line or at any other place in its length which has been reinforced, the strains will be borne by the reinforcing frame embedded in concrete or other cementitious material. ln reinforcing new poles, the flexible core may be inserted in place without expanding the same.

Further objects of the invention will hereinafter' appear and to these ends the invention consists of the method of reinforcing tubular or hollow structures and the structure so reinforced, substantially as hereinafter fully described and claimed in this specification and illustrated in the accompanying drawings, in which- Figure 1 is a sectional elevation of a trolley pole reinforced in accordance with our method; Fig. 2 is a sectional elevation of a trolley pole reinforced midway of its length Fig. 3 is a horizontal sectional view drawn to an enlarged scale on the line x, a of Fig. 1 Fig. 4 is a detail horizontal sectional view of a por- `We prefer to extion of ythe structure 5 Fig. 5 is an enlarged of the frame; Fig. 7 is a plan view of amodif4 fied form of core. Fig. 8 is a side view of said modification. Y

Referring to the drawings, we have illuse trated the invention in connection with a trolley pole, although we are not tobe understood as limiting the invention to this use, since it is applicable to other similar structures.

A represents a trolley ole structure as usual in three sections B, and D, of which B has the largest diameter and D the smallest diameter. The sections as shown are telescoped and the joints are preferably shrunk. This construction makes a tapering pole smaller in diameter at the top than at the bottom. The pole is usually provided with a suitable removable cap E. The lower section B is generally sunk in the ground F a suitable distance of about six feet, and G represents the ground line where the pole is apt to become weakened.

ln Fig. 1 we have shown the pole internally reinforced for a suitable distance above and below the ground line, while in Fig. 2 we have shown how it is possible to reinforce the pole at intermediate points, as for instance, the middle section C.

We preferably use a flexible core and for this purpose we have illustrated inv some of the figures a core substantially in the form of a stiff wire netting shown in Figs. 4 and 5 in detail views. The core should have great longitudinal stiffness and preferably comprises the longitudinal wires or rods H bound together by the transverse wires l of smaller diameter than the longitudinal members H, and secured to said members by the binding wires J. Such an articulated structure may be readily bought on the market and used for the purposes of this invention.

ln reinforcing a tapering structure such as a metallic trolley pole, it is necessary that the frame or core should` be flexible and capa'-V ble of being rolled into tubular form and ine serted through the smaller end of the pole after the cap E is removed. The type of frame or core shown in Figs. 4 and 5-is capable'of such use and will have a tendency to expand after insertion in proper position in the pole. In order, however, to insure that the core will expand into contact with the interior walls of the pole, we may use one or more flat metallic bands K wrapped within the frame or core to form springs for aiding the frame in expanding within the ole. Any other suitable springs may be used, fiowever, or other suitable means for expanding the core within the pole.

In carrying out our method of reinforce-y ment, we rst remove the cap E of the pole and then insert a frameor core fof material such as illustratedvin Figs. 4 and 5 tightly Vto expand aided by the springs K, will cause the material to assume substantially the position indicated in Fig. 3. The binding wires J will bear against the interior walls of the pole, thereby spacing the longitudinal or u right wires or rods H away from said walls, thus providing space Yfor the filling material ofconcrete to substantially surround the lon` gitudinal members H. lf desired, a suitable amount of concrete may first befpoured into the top of the pole to fill a short distance of the lower end of the pole as indicated at L Fig. l, so that the reinforcing frame will rest upon this filling. After the frame is in position and has been expanded, more concrete n or other cementitious material is poured into the top of the pole until the frame or core is substantially embedded in concrete.

Another frame or core may be inserted in section C as shown in Fig.l l, and telescoped for a suitable distance into the first frame inserted, as shown, thereby strengthening the pole to a still greater extent, and particularly at the juncture of the two frames.

In Fig. 2 the concrete L is first poured into Y the pole and as shown in this instance subassed down pressed air or water, through the tube'R after the frame is in position.

In Fig. 6 we have illustrated in detail horizontal sectional view, a modified form of longitudinal members H for the expansible frame. lln this modification, the said members HVare trapezoidal 1n cross sect1on,wh1ch provides more metal in a given space around j the inside walls of the pole, but sufficient spaces are left between the members H to nable the concrete to surround said memers. Y

In Fig. 7 another modification. of reinforce ing frame is shown in plan view, in which rods H are thrust through the linksQof suit'- able chains. lf desired,V the connecting members may be made of fabric or any suit-V able flexible material.

Our invention is designed when used in connection with trolley poles, to saveV theY labor and ex ense of replacing old poles with new ones. yA the use of our inventionhwe are enabled to reinforce and continue in use old poles which have become so weakened that it would otherwise be necessary to remove them and throw them in the scrap heap. Metallic trolley poles have come so universally into use, that the item of maintenance has become a serious and expensive one and our invention has for its object to reduce the cost of maintenance of old poles.

Our invention, of course, is equally applicable to the installation of new poles and similar structures and can be used when the structures are first installed as well as after they have been in use.

We claim and desire to obtain by Letters Patent the following:

1. The method substantially as herein described, of internally reinforcing a hollow structure, which consists in inserting a flexible reinforcing frame or core into the structure and expanding said frame or core therein, then embedding the frame or core in concrete or other cementitious material within the structure.

2. The method substantially as herein described, of internally reinforcing a hollow structure, which consists in inserting a resilient frame or core into the structure and expanding said frame or core therein, then embedding the frame or core in concrete or other cementitious material within the structure.

8. The method substantially as herein described, of internally reinforcing a hollow structure, which consists in inserting a ilexible articulated reinforcing frame or core into the structure and expanding said frame or core therein, then embedding the frame or core in concrete or other cementitious material within the structure.

4. rlhe method substantially as herein described, of internally reinforcing a hollow structure, which consists in inserting a flexible articulated reinforcing frame or core having longitudinal reinforcing members into the structure and expanding said frame or core therein, then embedding the frame or core in concrete or other cementitious material within the structure.

5. The method substantially as herein described, of internally reinforcing a hollow structure smaller at one end than the other, which consists in inserting a ilexible reinforcing frame or core through the smaller end of the structure into the larger portion thereof and expanding said frame or core v-Jithin the structure, and filling the portion of the structure so reinforced with concrete or other cementitious material.

6. The method substantially as herein described, of internally reinforcing a hollow structure smaller at one end than the other, which consists in first iilling the larger portion ofthe structure to the desired point with concrete or other cementitious material, then inserting a flexible reinforcing frame or core through the smaller end of the structure until said frame rests upon or lies in proximity to the concrete and expanding the frame within the structure, and finally embedding said frame or core in concrete or other cementitious material within the structure.

7. The method substantially as herein described, of internally reinforcing a hollow structure smaller at one end than the other, which consists in first `lilling the larger portion of the structure to the desired point with concrete or other cementitious material, then inserting a resilient frame or core through the smaller end of the structure until said frame rests upon or lies in proximity to the concrete and expanding the frame within the structure, and finally embedding said frame or core in concrete or other cementitious material within the structure.

8. The method substantially as herein described, of internally reinforcing a hollow structure smaller at one end than the other, which consists in inserting a resilient frame or core through the smaller end of the structure into the larger portion thereof and expanding said frame or core within the structure, and filling the portion of the structure so reinforced with concrete or other cementitious material.

9. The method substantially as herein described, of internally reinforcing at the ground line or other point of weakness a hollow metallic pole set in the ground, which consists in inserting a reinforcing core into the pole and locating said core with portions extending above and below the ground line or point of weakness, then embedding the core in concrete or other cementitious material within the structure.

l0. The method substantially as herein described, of internally reinforcing at the ground line or other point of weakness a hollow metallic pole set in the ground, which consists in inserting a reinforcing core into the pole through the upper end and locating said core adjacent the walls of the pole with portions of the core extending above and below the ground line or point of weakness, then embedding the core in concrete or other cementitious material.

ln testimony whereof we have signed this specification in the presence of the subscribing witnesses.

HERBERT H. HILBORN. CHARLES E. ROEHL.

Vllitnesses:

J J. HEFFERNAN, J. J. BADER, S. O. SPALDING, E. HENnRroKsoN. 

